DOCSLIB.ORG

Diachronous Development of Great Unconformities Before Neoproterozoic Snowball Earth

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Diachronous Development of Great Unconformities Before Neoproterozoic Snowball Earth Diachronous development of Great Unconformities before Neoproterozoic Snowball Earth Rebecca M. Flowersa,1, Francis A. Macdonaldb, Christine S. Siddowayc, and Rachel Havraneka aDepartment of Geological Sciences, University of Colorado, Boulder, CO 80309; bEarth Science Department, University of California, Santa Barbara, CA 93106; and cDepartment of Geology, The Colorado College, Colorado Springs, CO 80903 Edited by Paul F. Hoffman, University of Victoria, Victoria, Canada, and approved March 6, 2020 (received for review July 30, 2019) The Great Unconformity marks a major gap in the continental precisely because the Great Unconformities mark a large gap in geological record, separating Precambrian basement from Phan- the rock record, the erosion history leading to their formation erozoic sedimentary rocks. However, the timing, magnitude, cannot be investigated directly by study of preserved units. spatial heterogeneity, and causes of the erosional event(s) and/ Past work leads to at least four general models for the timing or depositional hiatus that lead to its development are unknown. and magnitude of pre-Great Unconformity continental erosion, We present field relationships from the 1.07-Ga Pikes Peak batho- which are depicted in Fig. 1. Some have proposed major erosion lith in Colorado that constrain the position of Cryogenian and of the continents associated with assembly of the supercontinent Cambrian paleosurfaces below the Great Unconformity. Tavakaiv Rodinia and mantle upwelling below it prior to 850 Ma (Hy- sandstone injectites with an age of ≥676 ± 26 Ma cut Pikes Peak pothesis 1) or with the early diachronous breakup of Rodinia granite. Injection of quartzose sediment in bulbous bodies indi- between 850 and 717 Ma (Hypothesis 2) (10–17). Others argue cates near-surface conditions during emplacement. Fractured, for an association with the Cryogenian Snowball Earth glacia- weathered wall rock around Tavakaiv bodies and intensely altered tions from 717 to 635 Ma (Hypothesis 3) (18–22). Still others basement fragments within unweathered injectites imply still ear- suggest that the appearance of animals and modern ecosystems lier regolith development. These observations provide evidence was the product of nutrient delivery via erosion and an increase that the granite was exhumed and resided at the surface prior in atmospheric oxygen at the Ediacaran–Cambrian transition at to sand injection, likely before the 717-Ma Sturtian glaciation for ca. 540 Ma (Hypothesis 4) related to the “transgressive buzzsaw” the climate appropriate for regolith formation over an extensive and subsequent burial (4, 5), later rifting of Laurentian margins region of the paleolandscape. The 510-Ma Sawatch sandstone di- (23, 24), or the Pan-African and Transantarctic orogenies and rectly overlies Tavakaiv-injected Pikes granite and drapes over construction of the supercontinent Pannotia (25, 26). core stones in Pikes regolith, consistent with limited erosion be- A critical question is if the Great Unconformity represents a tween 717 and 510 Ma. Zircon (U-Th)/He dates for basement be- single, global exhumation pulse (2, 4, 5) as the models above low the Great Unconformity are 975 to 46 Ma and are consistent typically assume, or if it is composite in origin (27). It is possible with exhumation by 717 Ma. Our results provide evidence that most that there are multiple Great Unconformities, which formed erosion below the Great Unconformity in Colorado occurred before over hundreds of millions of years due to diachronous regional the first Neoproterozoic Snowball Earth and therefore cannot be a tectonic phenomena. Multiple spatially heterogeneous exhuma- product of glacial erosion. We propose that multiple Great Uncon- tion events driven by several of the above mechanisms could formities developed diachronously and represent regional tectonic combine to generate one amalgamated gap of lengthy duration features rather than a synchronous global phenomenon. over a broad geographic scale. Arguments that Great Un- conformity erosion surface formation was a global phenomenon Great Unconformity | Snowball Earth | thermochronology | zircon (U-Th)/ use geochemical proxy data or preserved sediment volumes on He | injectites North America to indirectly infer erosion flux and nutrient de- livery across the Great Unconformity (2, 4, 5) rather than di- he Great Unconformity is an iconic geologic feature that rectly analyzing the age of the erosion surfaces. However, Tclassically marks the boundary between unfossiliferous Pre- interpretations of these geochemical records are nonunique, and cambrian rocks and fossiliferous Phanerozoic strata. To Charles the surfaces themselves are poorly dated. Deciphering the age of Darwin (1), the “sudden appearance” of complex macroscopic fossils in Cambrian strata necessitated a global stratigraphic Significance omission to reconcile the fossil record with Darwinian gradual- ism. Although subsequent concepts of extinction and radiation Erosion below the Great Unconformity has been interpreted as eliminated the need of a global time gap to explain the fossil a global phenomenon associated with Snowball Earth. Geo- record, the notion of a Late Neoproterozoic to Cambrian global logical relationships and thermochronologic data provide evi- unconformity has persisted (2–5). Particularly, the Great Un- dence that the bulk of erosion below the Great Unconformity conformity in North America, where the base of the Cambrian in Colorado occurred prior to Cryogenian glaciation. We sug- transgressive sequence commonly overlies Precambrian base- gest that there are multiple, regionally diachronous Great Un- ment (6), has been globally correlated with Late Neoproterozoic conformities that are tectonic in origin. to Cambrian unconformities on other continents (2–5). Recently, inferred erosion across these Great Unconformities has been Author contributions: R.M.F. and F.A.M. designed research; R.M.F., F.A.M., C.S.S., and R.H. associated with a variety of changes in the Earth System, in- performed research; and R.M.F., F.A.M., and C.S.S. wrote the paper. cluding the Neoproterozoic Snowball Earth (2), the initiation of Competing interest statement: P.F.H. and F.A.M. are coauthors on three papers, most modern plate tectonics (3), oxygenation of the ocean and at- recently in 2017. mosphere (4), and the Cambrian Explosion (5). However, the This article is a PNAS Direct Submission. timing, magnitude, and causes of erosion below the Great Un- Published under the PNAS license. conformities, and whether their development was globally syn- 1To whom correspondence may be addressed. Email: [email protected]. chronous or diachronous, are unknown. Although much work This article contains supporting information online at https://www.pnas.org/lookup/suppl/ has focused on Cambrian sedimentary records that locally rest on doi:10.1073/pnas.1913131117/-/DCSupplemental. older strata or that unconformably overlie basement (7–9), First published April 27, 2020. 10172–10180 | PNAS | May 12, 2020 | vol. 117 | no. 19 www.pnas.org/cgi/doi/10.1073/pnas.1913131117 Downloaded by guest on September 24, 2021 Routt and Berthoud plutonic suites (29). The batholith is dom- inated by the coarse-grained Pikes Peak granite (30) that was emplaced at 1,066 ± 10 Ma (31). The batholith likely crystallized at depths <5 km based on the low water content and late-stage crystallization temperatures of 720 °C to 700 °C estimated for the magmas and may even have breached the surface (32). Three areas within the batholith characterized by concentric flow structures may underpin former calderas, further supporting shallow batholith emplacement (29). At Pikes Peak, one of these intrusive centers encompasses the southern lobe of the batholith (29). Initial rapid cooling following Pikes Peak batholith em- placement is documented by 10 hornblende 40Ar/39Ar dates from Fig. 1. Hypothesized exhumation histories below the Great Unconformity. 1,080 ± 3 to 1,068 ± 2 Ma, 4 biotite 40Ar/39Ar plateau dates from Orange bars depict geological constraints from Colorado. Hypothesis 1 (H1) 1,079 ± 3 to 1,073 ± 2 Ma, and K-feldspar 40Ar/39Ar data that depicts major erosion of the continents associated with assembly of the ∼ supercontinent Rodinia and mantle upwelling below it (14, 17). Hypothesis 2 suggest low-temperature cooling by 1,000 Ma (33). An apatite (H2) depicts major erosion associated with the early breakup of Rodinia (10–13, 15, 16). Hypothesis 3 (H3) depicts an association with the Cryogenian Snowball Earth glaciations (18–22). Hypothesis 4 (H4) depicts major erosion associated with the Cambrian transgressive buzzsaw and subsequent burial (4, 5), later rifting of Laurentian margins (23, 24), or the Pan-African orogeny and Transantarctic orogenies and construction of the supercontinent Pannotia (25, 26). An alternative hypothesis is that there are multiple Great Unconfor- mities representing diachronous regional phenomena, and these features de- veloped predominantly on Laurentia and its conjugate rifted margins. the Great Unconformity at specific localities by constraining Precambrian basement exhumation histories prior to Paleozoic overlap assemblages is required to test the competing hypotheses EARTH, ATMOSPHERIC, AND PLANETARY SCIENCES for Great Unconformity formation and tease out potential complexities in its origins. Recent work has used advances in thermochronology to con- strain major cooling events preceding Great Unconformity de- velopment in the Ozark Mountains of the central
Load more

Recommended publications
  • The Huronian Glaciation
    Brasier, A.T., Martin, A.P., Melezhik, V.A., Prave, A.R., Condon, D.J., and Fallick, A.E. (2013) Earth's earliest global glaciation? Carbonate geochemistry and geochronology of the Polisarka Sedimentary Formation, Kola Peninsula, Russia. Precambrian Research, 235 . pp. 278-294. ISSN 0301-9268 Copyright © 2013 Elsevier B.V. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge Content must not be changed in any way or reproduced in any format or medium without the formal permission of the copyright holder(s) When referring to this work, full bibliographic details must be given http://eprints.gla.ac.uk/84700 Deposited on: 29 August 2013 Enlighten – Research publications by members of the University of Glasgow http://eprints.gla.ac.uk 1 Earth’s earliest global glaciation? Carbonate geochemistry and geochronology of the 2 Polisarka Sedimentary Formation, Kola Peninsula, Russia 3 4 A.T. Brasier1,6*, A.P. Martin2+, V.A. Melezhik3,4, A.R. Prave5, D.J. Condon2, A.E. Fallick6 and 5 FAR-DEEP Scientists 6 7 1 Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV 8 Amsterdam 9 2 NERC Isotope Geosciences Laboratory, British Geological Survey, Environmental Science 10 Centre, Keyworth, UK. NG12 5GG 11 3 Geological Survey of Norway, Postboks 6315 Slupen, NO-7491 Trondheim, Norway 12 4 Centre for Geobiology, University of Bergen, Postboks 7803, NO-5020 Bergen, Norway 13 5 Department of Earth and Environmental Sciences, University of St Andrews, St Andrews KY16 14 9AL, Scotland, UK 15 6 Scottish Universities Environmental Research Centre, Rankine Avenue, East Kilbride, Scotland.
    [Show full text]
  • Bailey Mark Hopkins 1980
    AN ABSTRACT OF THE THESIS OF MARK H. BAILEY for the degree of Master of Science in Geology presented on June 7, 1979 Title: BEDROCK GEOLOGY OF WESTERN TAYLOR PARK, GUNNISON COUNTY, COLORADO Signature redacted for privacy. Abstract approved: I ._&V_j - Dr. Robert D. Lawrence The western Taylor Park area covers about 65 square miles on the western flank of the Sawatch Range. It is underlain chiefly by Precambrian rocks, partiallycovered on the east by glacial debris andoverlapped on the west and south by Paleozoic sedimentary rocks. The Precambrian rocks include a group ofmetasedimen- tary rocks of an undetermined age greaterthan 1700 m.y. The metasedimentary rocks include five mineralogicallydis- tinct units, quartzite, quartz-muscovite schist, quartz- epidote schist, quartz-plagioclase-biotite schist,and quartz-biotite-microcline-sillimaflite schist. The higher grade sillimanite-bearing biotite schists arerestricted to the western half of the map area and closelyassociated with the Forest Hill granitic rocks. The metasedimentary rocks were intruded twiceduring Precambrian time. The oldest intrusive event resulted in syntectonic emplacement of granodiorite and biotite tona- lite rocks. These rocks correlate with the 1700 m.y.old Denny Creek granodiorite gneiss and Kroenkegranodiorite which are mapped and informally named in the adjoining Mount Harvard quadrangle. The second, post-tectonic, igneous eventproduced granitic rocks that are dated at 1030 m.y. byRb-Sr meth- ods. These rocks include two comagmatic graniticphases, the Forest Hill porphyritic granite and the ForestHill cataclastic granite. A third phase, the Forest Hill horn- blende granodiorite, intrudes the porphyritic graniteand, therefore, is younger than the granitic phases. The 1030 m.y.
    [Show full text]
  • Neoproterozoic Glaciations in a Revised Global Palaeogeography from the Breakup of Rodinia to the Assembly of Gondwanaland
    Sedimentary Geology 294 (2013) 219–232 Contents lists available at SciVerse ScienceDirect Sedimentary Geology journal homepage: www.elsevier.com/locate/sedgeo Invited review Neoproterozoic glaciations in a revised global palaeogeography from the breakup of Rodinia to the assembly of Gondwanaland Zheng-Xiang Li a,b,⁎, David A.D. Evans b, Galen P. Halverson c,d a ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) and The Institute for Geoscience Research (TIGeR), Department of Applied Geology, Curtin University, GPO Box U1987, Perth, WA 6845, Australia b Department of Geology and Geophysics, Yale University, New Haven, CT 06520-8109, USA c Earth & Planetary Sciences/GEOTOP, McGill University, 3450 University St., Montreal, Quebec H3A0E8, Canada d Tectonics, Resources and Exploration (TRaX), School of Earth and Environmental Sciences, University of Adelaide, SA 5005, Australia article info abstract Article history: This review paper presents a set of revised global palaeogeographic maps for the 825–540 Ma interval using Received 6 January 2013 the latest palaeomagnetic data, along with lithological information for Neoproterozoic sedimentary basins. Received in revised form 24 May 2013 These maps form the basis for an examination of the relationships between known glacial deposits, Accepted 28 May 2013 palaeolatitude, positions of continental rifting, relative sea-level changes, and major global tectonic events Available online 5 June 2013 such as supercontinent assembly, breakup and superplume events. This analysis reveals several fundamental ’ Editor: J. Knight palaeogeographic features that will help inform and constrain models for Earth s climatic and geodynamic evolution during the Neoproterozoic. First, glacial deposits at or near sea level appear to extend from high Keywords: latitudes into the deep tropics for all three Neoproterozoic ice ages (Sturtian, Marinoan and Gaskiers), al- Neoproterozoic though the Gaskiers interval remains very poorly constrained in both palaeomagnetic data and global Rodinia lithostratigraphic correlations.
    [Show full text]
  • CRETACEOUS-TERTIARY BOUNDARY Ijst the ROCKY MOUNTAIN REGION1
    BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA V o l..¿5, pp. 325-340 September 15, 1914 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY CRETACEOUS-TERTIARY BOUNDARY IjST THE ROCKY MOUNTAIN REGION1 BY P. H . KNOWLTON (Presented before the Paleontological Society December 31, 1913) CONTENTS Page Introduction........................................................................................................... 325 Stratigraphic evidence........................................................................................ 325 Paleobotanical evidence...................................................................................... 331 Diastrophic evidence........................................................................................... 334 The European time scale.................................................................................. 335 Vertebrate evidence............................................................................................ 337 Invertebrate evidence.......................................................................................... 339 Conclusions............................................................................................................ 340 I ntroduction The thesis of this paper is as follows: It is proposed to show that the dinosaur-bearing beds known as “Ceratops beds,” “Lance Creek bieds,” Lance formation, “Hell Creek beds,” “Somber beds,” “Lower Fort Union,”- Laramie of many writers, “Upper Laramie,” Arapahoe, Denver, Dawson, and their equivalents, are above a major
    [Show full text]
  • 2018-5 PGS Newsletter
    SEPTEMBER 2018 PGS NEWSLETTER VOL LXXI NO 1 September 12, 2018 Tectonics of the Social hour 6:00 PM Midcontinent: Looking Dinner 7:00 PM West (Geologically) Program 8:00 PM Dinner costs from Pittsburgh $30.00 per person $10.00 student member Across the Craton Reservations Email your name and number of attendees in your party to: pgsreservations @gmail.com You can also reserve and pay via PayPal at: https://www.pittsburgh geologicalsociety.org/ Dr. Stephen Marshak Location Foster’s Restaurant University of Illinois, Urbana-Champaign Foster Plaza Bldg. 10 Green Tree PA Deadline for reservations is noon on Monday, Sept. 10. Speaker Abstract Geologists have long held a fascination with and magnetotelluric arrays) that serve to mountain belts, because of their scenic beauty, characterize variations in crustal thickness, the and because they offer cross sections that intensity of faulting, and the relationship of provide access to rocks once deep in the crust. seismicity to structure; 2) structure-contour Datable igneous and metamorphic rocks in maps that help characterize the nature of mountain belts provide a basis for developing a displacement in fault-and-fold zones; 3) chronology of tectonism. The USA subsidence curves that constrain the timing of Midcontinent region doesn't display such basin subsidence; 4) a digital elevation model drama. These interior plains, which extend (DEM) of the Great Unconformity (the contact from Pittsburgh west to the Rockies, are part of between Precambrian and Paleozoic strata), North America's cratonic platform, a region in that gives a clearer image of structural relief which crust that formed over 1 billion years ago between basins and domes; 5) results from a lies buried beneath a veneer of nearly flat-lying thermochronologic study of the Great Phanerozoic sedimentary strata.
    [Show full text]
  • PEAK to PRAIRIE: BOTANICAL LANDSCAPES of the PIKES PEAK REGION Tass Kelso Dept of Biology Colorado College 2012
    !"#$%&'%!(#)()"*%+'&#,)-#.%.#,/0-#!"0%'1%&2"%!)$"0% !"#$%("3)',% &455%$6758% /69:%8;%+<878=>% -878?4@8%-8776=6% ABCA% Kelso-Peak to Prairie Biodiversity and Place: Landscape’s Coat of Many Colors Mountain peaks often capture our imaginations, spark our instincts to explore and conquer, or heighten our artistic senses. Mt. Olympus, mythological home of the Greek gods, Yosemite’s Half Dome, the ever-classic Matterhorn, Alaska’s Denali, and Colorado’s Pikes Peak all share the quality of compelling attraction that a charismatic alpine profile evokes. At the base of our peak along the confluence of two small, nondescript streams, Native Americans gathered thousands of years ago. Explorers, immigrants, city-visionaries and fortune-seekers arrived successively, all shaping in turn the region and communities that today spread from the flanks of Pikes Peak. From any vantage point along the Interstate 25 corridor, the Colorado plains, or the Arkansas River Valley escarpments, Pikes Peak looms as the dominant feature of a diverse “bioregion”, a geographical area with a distinct flora and fauna, that stretches from alpine tundra to desert grasslands. “Biodiversity” is shorthand for biological diversity: a term covering a broad array of contexts from the genetics of individual organisms to ecosystem interactions. The news tells us daily of ongoing threats from the loss of biodiversity on global and regional levels as humans extend their influence across the face of the earth and into its sustaining processes. On a regional level, biologists look for measures of biodiversity, celebrate when they find sites where those measures are high and mourn when they diminish; conservation organizations and in some cases, legal statutes, try to protect biodiversity, and communities often struggle to balance human needs for social infrastructure with desirable elements of the natural landscape.
    [Show full text]
  • Denudation History and Internal Structure of the Front Range and Wet Mountains, Colorado, Based on Apatite-Fission-Track Thermoc
    NEW MEXICO BUREAU OF GEOLOGY & MINERAL RESOURCES, BULLETIN 160, 2004 41 Denudation history and internal structure of the Front Range and Wet Mountains, Colorado, based on apatite­fission­track thermochronology 1 2 1Department of Earth and Environmental Science, New Mexico Institute of Mining and Technology, Socorro, NM 87801Shari A. Kelley and Charles E. Chapin 2New Mexico Bureau of Geology and Mineral Resources, New Mexico Institute of Mining and Technology, Socorro, NM 87801 Abstract An apatite fission­track (AFT) partial annealing zone (PAZ) that developed during Late Cretaceous time provides a structural datum for addressing questions concerning the timing and magnitude of denudation, as well as the structural style of Laramide deformation, in the Front Range and Wet Mountains of Colorado. AFT cooling ages are also used to estimate the magnitude and sense of dis­ placement across faults and to differentiate between exhumation and fault­generated topography. AFT ages at low elevationX along the eastern margin of the southern Front Range between Golden and Colorado Springs are from 100 to 270 Ma, and the mean track lengths are short (10–12.5 µm). Old AFT ages (> 100 Ma) are also found along the western margin of the Front Range along the Elkhorn thrust fault. In contrast AFT ages of 45–75 Ma and relatively long mean track lengths (12.5–14 µm) are common in the interior of the range. The AFT ages generally decrease across northwest­trending faults toward the center of the range. The base of a fossil PAZ, which separates AFT cooling ages of 45– 70 Ma at low elevations from AFT ages > 100 Ma at higher elevations, is exposed on the south side of Pikes Peak, on Mt.
    [Show full text]
  • The History of Ice on Earth by Michael Marshall
    The history of ice on Earth By Michael Marshall Primitive humans, clad in animal skins, trekking across vast expanses of ice in a desperate search to find food. That’s the image that comes to mind when most of us think about an ice age. But in fact there have been many ice ages, most of them long before humans made their first appearance. And the familiar picture of an ice age is of a comparatively mild one: others were so severe that the entire Earth froze over, for tens or even hundreds of millions of years. In fact, the planet seems to have three main settings: “greenhouse”, when tropical temperatures extend to the polesand there are no ice sheets at all; “icehouse”, when there is some permanent ice, although its extent varies greatly; and “snowball”, in which the planet’s entire surface is frozen over. Why the ice periodically advances – and why it retreats again – is a mystery that glaciologists have only just started to unravel. Here’s our recap of all the back and forth they’re trying to explain. Snowball Earth 2.4 to 2.1 billion years ago The Huronian glaciation is the oldest ice age we know about. The Earth was just over 2 billion years old, and home only to unicellular life-forms. The early stages of the Huronian, from 2.4 to 2.3 billion years ago, seem to have been particularly severe, with the entire planet frozen over in the first “snowball Earth”. This may have been triggered by a 250-million-year lull in volcanic activity, which would have meant less carbon dioxide being pumped into the atmosphere, and a reduced greenhouse effect.
    [Show full text]
  • Analysis and Correlation of Growth
    ANALYSIS AND CORRELATION OF GROWTH STRATA OF THE CRETACEOUS TO PALEOCENE LOWER DAWSON FORMATION: INSIGHT INTO THE TECTONO-STRATIGRAPHIC EVOLUTION OF THE COLORADO FRONT RANGE by Korey Tae Harvey A thesis submitted to the Faculty and Board of Trustees of the Colorado School of Mines in partial fulfillment of the requirements for the degree of Master of Science (Geology). Golden, Colorado Date __________________________ Signed: ________________________ Korey Harvey Signed: ________________________ Dr. Jennifer Aschoff Thesis Advisor Golden, Colorado Date ___________________________ Signed: _________________________ Dr. Paul Santi Professor and Head Department of Geology and Geological Engineering ii ABSTRACT Despite numerous studies of Laramide-style (i.e., basement-cored) structures, their 4-dimensional structural evolution and relationship to adjacent sedimentary basins are not well understood. Analysis and correlation of growth strata along the eastern Colorado Front Range (CFR) help decipher the along-strike linkage of thrust structures and their affect on sediment dispersal. Growth strata, and the syntectonic unconformities within them, record the relative roles of uplift and deposition through time; when mapped along-strike, they provide insight into the location and geometry of structures through time. This paper presents an integrated structural- stratigraphic analysis and correlation of three growth-strata assemblages within the fluvial and fluvial megafan deposits of the lowermost Cretaceous to Paleocene Dawson Formation on the eastern CFR between Colorado Springs, CO and Sedalia, CO. Structural attitudes from 12 stratigraphic profiles at the three locales record dip discordances that highlight syntectonic unconformities within the growth strata packages. Eight traditional-type syntectonic unconformities were correlated along-strike of the eastern CFR distinguish six phases of uplift in the central portion of the CFR.
    [Show full text]
  • To Download Elementary School Geology Packet
    Garden of the Gods Park Contact: Bowen Gillings City of Colorado Springs Parks, Recreation & Cultural Services Email: [email protected] P: (719) 219-0108 Program updates can be found at: https://gardenofgods.com/educational/edu- 1/school-field-trips Land Use Acknowledgement: We gratefully acknowledge the native peoples on whose ancestral homeland we gather, as well as the diverse and vibrant Native communities of Colorado today. Geology of the Park Program Welcome! We look forward to sharing the geological story of Garden of the Gods with your students. We align with current Colorado Academic Standards for K-5 Earth and Space Science. Goals: Students recognize the exceptional geological wonder of the Garden of the Gods. Students gain a broad understanding of the geological events that shaped the Pikes Peak region Students gain a broad understanding of and appreciation for the science of geology. Students identify the three rock types and the three geological processes. Students recognize the geological formations in the Park, their ages, and composition. 1 Teacher Reference Guide: Basic Geology of Garden of the Gods The Pike’s Peak region has been shaped by millions of years of mountain building and erosion. There have been three different mountain building events in the geological history of this area: 1. The Ancestral Rockies (320-310 million years ago). The erosion of these first Rocky Mountains formed the sedimentary Fountain Formation and the Lyons Sandstone layers. 2. The Laramide Orogeny (70-65 million years ago). This process uplifted the Front Range. The layers seen in the Garden were forced upright as the land broke along the Rampart Range Fault.
    [Show full text]
  • Stratigraphy of the Project Area
    I BRITISH &! COLUMBLA Ministry of Employment and Investment ENERGY AND MINERALS DIVISION Hon. Dan Miller. Minister Geological Survey Branch THE STIKINE PROJECT GEOLOGY OF WESTERN TELEGRAPH CREEK MAP AREA, NORTHWESTERN BRITISH COLUMBIA (NTS 104G/5,6, llW, 12 AND 13) By Derek A. Brown1 , Michael H. Gunning2 and Charles J. Greig3 Appendix 3 - Conodont identifications by "I. Orchard, Geological Survey of Canada 1. Geological Surve Branch, British Colunlhia Ministry of Employment andYlnvestment 2. Department of Geology, University of Western Ontario, London, Ontario 3. C.G. Greig and Associates Ltd., Penticton, B.C. BULLETIN 95 Canadian Cataloguing in Publication Data Brawn. Derek Anlhony. 1959- The Stikine project : geology of western Telegraph Creek map area. nonhwenlem British Columbia (NTS.lMG15. 6, IIW. 12and 13) Issued by Geological Survey Branch. Includes bibliographical references: p ISBN 0-7726-2502-6 1, Geology -British Columbia -Telegraph Creek Region 2. Geochemistry - British Columbia - Telegraph Creek VICTORIA Region. 3. Geology. Economic - British Columbia - BRITISH COLUMBIA Telegraph Creek Region. 4. Mines and mineral resources - CANADA British Columbia - Telegraph Creek Region. 1. Gunning. Michael H. 11. Greig.Charles James, 1956- . 111. British Columbia. Ministry of Employment and Investmenl. IV. MAY 1996 BritishColumbia. Geological Survey Branch. V. Title. VI. Title: Geology of western Telegraph Creek maparea, nanhwertern British Columbia (NTS 1WG15.6. 1 IW. 12 and 13). V11. Series: Bulletin (British Columbia. Ministry of Employment and Investment) ;95. QE187.B76 1996 557.11’185 (395-960208-9 Frontispiece. View north along the Scud Glacier. Ambition Mountainis underlain by Permian limestone and metavolcanic rocks. Ministry of Emp/oyment and Inveshent TABLE OF CONTENTS CHAPTER 1 Chemistry .....................
    [Show full text]
  • Geologic Studies of the Platte River, South-Central Nebraska and Adjacent Areas—Geologic Maps, Subsurface Study, and Geologic History
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Publications of the US Geological Survey US Geological Survey 2005 Geologic Studies of the Platte River, South-Central Nebraska and Adjacent Areas—Geologic Maps, Subsurface Study, and Geologic History Steven M. Condon Follow this and additional works at: https://digitalcommons.unl.edu/usgspubs Part of the Earth Sciences Commons Condon, Steven M., "Geologic Studies of the Platte River, South-Central Nebraska and Adjacent Areas—Geologic Maps, Subsurface Study, and Geologic History" (2005). Publications of the US Geological Survey. 22. https://digitalcommons.unl.edu/usgspubs/22 This Article is brought to you for free and open access by the US Geological Survey at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Publications of the US Geological Survey by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Geologic Studies of the Platte River, South- Central Nebraska and Adjacent Areas—Geologic Maps, Subsurface Study, and Geologic History Professional Paper 1706 U.S. Department of the Interior U.S. Geological Survey Geologic Studies of the Platte River, South-Central Nebraska and Adjacent Areas—Geologic Maps, Subsurface Study, and Geologic History By Steven M. Condon Professional Paper 1706 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior Gale A. Norton, Secretary U.S. Geological Survey Charles G. Groat, Director Version 1.0, 2005 This publication and any updates to it are available online at: http://pubs.usgs.gov/pp/pp1706/ Manuscript approved for publication, March 3, 2005 Text edited by James W. Hendley II Layout and design by Stephen L.
    [Show full text]